PC World reports that its forum users are, in some cases, seeing big chunks of their hard drives freed up after installing Vista Service Pack 2. It might be due to old Restore Points being wiped out, or because it runs a command-line cleaning tool, compcln.exe, but a good number of (successful) SP2 installers report tens of gigabytes opening up. Looking to reclaim more storage space on your system, Vista or otherwise? Try our multi-platform guide to visualizing and optimizing hard drive usage. [PC World]